The wheel speed is the main input signal of the ABS system, and the collection and processing of this signal are crucial for the control of the entire system. In order to make the collected wheel speed signal can be correctly recognized by the single chip microcomputer, the Hall sensor used in this system is made of the sensor and the signal processing circuit. Because it can directly output the standard square wave signal, it is very suitable for HIS high-speed channel acquisition , The four HIS ports of 80c196kc can directly receive the pulse signals of four wheel speed sensors, and can simultaneously record the state and time when a certain time is triggered.